Research Areas > Millennium Nucleus ERIS

Millennium Nucleus ERIS

The Millennium Nucleus ERIS (Evolutionary Reconstruction of the InterStellar medium) will apply one of the principles of Darwin’s Theory of Evolution – descent with modification – to cosmic evolution and is lead by Paula Jofre (Director) and Evelyn Johnston (PI) from AstroUDP, together with Patricia Tissera (co-director) and Alvaro Rojas (PI) from Universidad Santiago.
The fundamental tool (phylogenetic tree) is already extensively used in other evolutionary studies on Earth. Since trees are mathematical structures and graphs, with ERIS we will consolidate an interdisciplinary collaboration between astronomers, biologists and mathematicians, in order to achieve our scientific goals. We will reconstruct the evolution of galaxies by building and interpreting phylogenetic trees that are appropriate for astronomical data. To do so, we will simulate the evolution of galaxies, where we know their shared history. We will also use observed data, which will allow us to learn to deal with uncertainties.
The key to connect stars with one another is the well known fact that massive stars synthesize chemical elements in their interiors, and at the end of their lives, by exploding they pollute the interstellar clouds from which new stars form. Chemically processed gas is what one generation of stars inherit from the previous one(s) and are the key observable for us to build the phylogenetic trees. Our strength is the fact that we know very robustly what elements are produced in which type of stars, and how much of them. The challenge is the fact that a galaxy is an open system: fresh gas comes from outside all the time, diluting the existing one. Also, different generations of stars contribute to the pollution of the same interstellar clouds. Therefore, the problem is manifold and intricate, just like the biological evolution of species.
More information:
UDP members: Paula Jofre, Evelyn Johnston, Danielle de Brito Silva, Keerthana Jegatheesan, Sara Vitali, Kacper Mielniczuk, Camilla Eldridge, Scarlet Elgueta, Claudia Aguilera, Theosamuele Signor
Contact person: Paula Jofre